Alessandro Maria Michetti

1. Introduction The Sannio–Matese area (Southern Italy) (Figure 1) is one of the most seismically active zones in the Southern Apennines, characterized by historical seismicity of high energy focused along NW-SE-trending faults, e.g., [1,2,3,4,5,6,7] and by low-to-medium energy seismic swarms across structures transverse to the chain in more recent times, e.g., [8,9,10,11].